The BLACKTHORN: a hidden whiskey classic cocktail

Two classic Blackthorn cocktails from the early 1900s, mixed side by side. The Irish Blackthorn (Harry Johnson, 1900) is a vermouth-forward Irish whiskey cocktail with absinthe and Boker's-style cardamom bitters. The Blackthorn #2 (William 'Cocktail' Boothby, 1908) is an equal-parts sloe gin, sweet vermouth, and dry/blanc vermouth cocktail with orange and Angostura bitters. Both are stirred, strained into chilled cocktail glasses, and finished with expressed lemon oil.

smart_display Published 2026-02-28 download Extracted 2026-05-13

5m Prep

5m Total

1 Servings

cocktail whiskey irish-whiskey sloe-gin vermouth classic-cocktail stirred absinthe bitters no-cook

Ingredients

The Blackthorn #2

22.5 ml Plymouth Sloe Gin
22.5 ml Dolin Sweet Vermouth de Chambéry
22.5 ml Dolin Blanc Vermouth de Chambéry
2 dashes Regan's Orange Bitters No. 6
1 dash Angostura Bitters
1 piece lemon peel (expressed over the top)

The Irish Blackthorn

45 ml Redbreast 12 year Irish Whiskey
45 ml Dolin Blanc Vermouth de Chambéry
2 dashes St. George Absinthe Verte
3 dashes Fee Bros. Cardamom (Boker's Style) Bitters
1 piece lemon peel (expressed and used as garnish)

Steps

The Blackthorn #2

1

In a mixing glass, add 3/4 oz (22.5 ml) sloe gin, 3/4 oz (22.5 ml) sweet vermouth, and 3/4 oz (22.5 ml) blanc vermouth.

Tip: If using a richer sweet vermouth like Cocchi Vermouth di Torino or Carpano Antica, cut the sweet vermouth back slightly — Anders prefers a lighter sweet vermouth here.

~1 min
2

Add 2 full dashes of orange bitters and 1 full dash of Angostura bitters.

~1 min
3

Add ice and stir until very cold.

~1 min
4

Strain into a chilled stemmed cocktail glass. Express lemon oil across the top, hit the sides of the glass with the peel, then discard.

Tip: A round, berry-shaped glass nods to the sloe berry — a fun visual cue for this version.

~1 min

The Irish Blackthorn

1

In a mixing glass, add 1.5 oz (45 ml) Irish whiskey, 1.5 oz (45 ml) blanc vermouth, 2 full dashes of absinthe, and 3 full dashes of Boker's-style cardamom bitters.

Tip: Anders uses Redbreast 12 year — a finer Irish whiskey makes a noticeably better cocktail than budget options.

~1 min
2

Add ice to the mixing glass and stir until well chilled.

Tip: As soon as the ice hits and you start stirring, the absinthe aroma is the first thing you'll smell.

~1 min
3

Strain into a chilled cocktail glass. Express lemon oil across the top, rub the peel around the rim, and garnish with the peel.

~1 min

Nutrition (per serving)

200

Calories

Carbs

Cultural Context

The Blackthorn cocktail has a tangled history dating to 1900, when Harry Johnson first printed a recipe in his Bartender's Manual using Irish whiskey, French vermouth, absinthe, and Boker's bitters. In 1908, William 'Cocktail' Boothby published a completely different drink under the same name in The World's Drinks and How to Mix Them — a sloe gin and equal-parts vermouth cocktail credited to a William Smith. The name 'blackthorn' connects naturally to the second recipe, since sloe berries grow on the blackthorn bush. By the 1920s and 30s, cocktail books like Robert Vermiere's 1922 Cocktails: How to Mix Them and Trader Vic's 1947 Bartender's Guide listed multiple, contradictory Blackthorn recipes, cementing the confusion. The Irish whiskey version regained popularity through Gary Regan's 2003 The Joy of Mixology, which adapted Harry Craddock's Savoy Cocktail Book version into a Manhattan-style ratio.